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1.
目的 筛选赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对炎症反应的抑制作用最强的流份。 方法 使用MTT法确定壮药赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对RAW264.7细胞安全给药浓度范围,通过ELISA法测定赪桐乙酸乙酯部位及不同洗脱梯度二氯甲烷-甲醇部位对LPS诱导RAW264.7细胞分泌NO、TNF-a、IL-12、IL-6、IL-1β含量,筛选对炎症反应的抑制作用最强的流份。 结果 赪桐乙酸乙酯部位及流份在0.06~2.0 mg/ml浓度范围内,赪桐乙酸乙酯部位及流份对细胞活力的抑制作用逐渐增强,浓度在0.5 mg/ml以上具有明显的细胞毒性,在0.5 mg/ml以下对细胞活力具有增强作用。二氯甲烷-甲醇洗脱部位高剂量能抑制炎症因子IL-12、IL-6、TNF-a、IL-1β释放,对NO的分泌没有抑制作用。 结论 赪桐乙酸乙酯部位及不同洗脱梯度的二氯甲烷-甲醇部位抗炎机制是通过抑制NO、TNF-a、IL-12、IL-6、IL-1β炎症因子的分泌,二氯甲烷-甲醇(50:1)洗脱部位和二氯甲烷-甲醇(30:1)洗脱部位的抗炎能力较强。  相似文献   
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The family Falconidae has contrasting behaviors on its flight within the subfamilies. Falcons are primarily aerial predators requiring accuracy, high speed, and controlled movements during flight. Caracaras are generalists that seek food while walking and their flight is characterized as slow and erratic. We aimed to explore the muscle mass of the primary wing muscles in several species of Falconinae and to identify possible differences related to the role that these muscles perform during flight. We studied 34 wing muscles in 11 specimens of five species of falcons. The percentage of each muscle with respect to body mass was calculated as well as the total wing muscle mass. The search for differences between muscles of falcons and caracaras was analyzed using Bayesian statistical inference. Published data from Polyborinae were used for comparison. Five muscles were significantly different between both subfamilies mm. latissimus dorsi pars caudalis, biceps brachii, extensor carpi radialis, flexor digitorum superficialis, and extensor digitorum communis. The first two muscles were larger in Polyborinae, which could be useful to achieve more strength and stabilization. In falcons the last three muscles listed were larger, which might be associated with their fast and acrobatic flight. Variations in certain muscles generate, in turn, differences in function, which is reflected in their type of flight and its use. These findings reinforce the modular character of the locomotor system of birds whereby the regions involved in locomotion can have morphological peculiarities according to their lifestyle.  相似文献   
3.
Alveolar soft part sarcoma is a rare highly malignant neoplasm of the soft tissue and usually occurs in the lower extremities of children and young adults. We report two cases of alveolar soft part sarcoma: a 24‐year‐old Latino man with a 10‐ cm neck mass and a 56‐year‐old Latino woman with a recurring thigh mass. Fine‐needle aspiration and a core biopsy were performed on both, which was followed by tumor resection on the man. The smears displayed numerous loosely cohesive or single large cells with abundant granular cytoplasm, round nuclei, vesicular chromatin, and occasional prominent nucleoli. Periodic and Schiff (PAS)‐positive, diastase‐resistant rhomboid, or needle‐shaped crystals were present. Both tumors had diffuse and strong nuclear TFE3 expression and aberrant cytoplasmic CD68 expression. Fluorescence in situ hybridization analysis was performed in the first case, which detected a characteristic translocation t(X;17)(p11;q25). The diagnosis of alveolar soft part sarcoma was rendered in both cases. Herein, we present the cytology, histology, immunohistochemistry, and molecular findings and discuss the differential diagnosis.  相似文献   
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滇重楼地上部分总皂苷HPLC指纹图谱   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:建立滇重楼地上部分总皂苷高效液相色谱法(HPLC)指纹图谱,为滇重楼地上部分总皂苷的质量控制提供参考。方法:采用Ecosil HPLC C18色谱柱(250 mm×4.6 mm,5μm)进行分离,流动相为乙腈-水溶液,梯度洗脱,流速为1.0 mL·min-1,检测波长为203 nm,柱温为31℃。建立6批滇重楼地上部分总皂苷HPLC特征图谱,并进行相似度评价;采用硅胶、反向硅胶RP-C18柱色谱等方法对特征图谱中的3个未知共有峰化合物进行分离,应用质谱法(MS)、核磁共振(NMR)等方法进行结构鉴定;参照各对照品的色谱行为及其二极管阵列检测器(DAD)紫外光谱图,对共有峰进行归属和指认。结果:指纹图谱中的3个未知共有峰化合物为偏诺皂苷元-3-O-α-L-吡喃鼠李糖基-(1→4)-[α-L-吡喃鼠李糖基-(1→4)-β-D-吡喃葡萄糖苷(cld01)、偏诺皂苷元-3-O-α-L-吡喃鼠李糖基-(1→4)-β-D-吡喃葡萄糖苷(cld02)、薯蓣皂苷元-3-O-α-L-吡喃鼠李糖基-(1→4)-[α-L-吡喃鼠李糖基-(1→4)-β-D-吡喃葡萄糖苷(cld03)。cld02为首次从该植物中分离得到,cld03为首次从该植物地上部分分离得到;6批样品特征图谱与对照图谱的相似度均大于0.99,共归属指认了7个共有峰。结论:所建立的HPLC指纹图谱方法稳定、可靠、重复性好,可为滇重楼地上部分总皂苷质量控制提供参考。  相似文献   
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The classification of the distinct group of mesenchymal neoplasms, first described as ‘Xp11 translocation perivascular epithelioid cell tumor (PEComa)’ and for which the term ‘melanotic Xp11 neoplasm’ or ‘Xp11 neoplasm with melanocytic differentiation’ has recently been proposed, remains challenging and controversial. We collected 27 melanotic Xp11 neoplasms, the largest series to date, for a comprehensive evaluation. Fourteen of the cases, together with eight alveolar soft part sarcomas (ASPS), nine conventional PEComas and a control group of seven normal tissues were submitted to RNA sequencing. Follow-up available in 22 patients showed 5-year overall survival and 5-year disease-free survival of 47.6 and 35.7%, respectively, which were similar to ASPS and significantly worse than conventional PEComa. Univariate analysis of location (occurring in the kidney versus not kidney), infiltrative growth pattern, nuclear pleomorphism, mitotic activity ≥2/50 high-power fields (HPF), necrosis and lymphovascular invasion were found to be associated with overall survival and/or disease-free survival. Multivariate analysis identified that location was the only factor found to independently correlate with disease-free survival. More importantly, RNA sequencing-based clustering analysis segregated melanotic Xp11 neoplasm and ASPS from other tumors, including conventional PEComa and Xp11 translocation renal cell carcinoma, and formed a compact cluster representative of the largely similar expression signature. Here we clearly define the true biologic nature of melanotic Xp11 neoplasms which are distinctive malignant mesenchymal tumors, rather than simply PEComa variants with occasionally unpredictable behavior. Meanwhile, melanotic Xp11 neoplasm and ASPS more likely represent phenotypic variants of the same entity, which is distinct from conventional PEComa and Xp11 translocation renal cell carcinoma. Based on these important findings, melanotic Xp11 neoplasm might be reclassified into a distinctive entity together with ASPS, independent from PEComa, in future revisions of the current WHO categories of tumors of soft tissue and bone for the improved reclassification. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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Background and objectiveBurns are a serious health problem leading to several thousand deaths annually, and despite the growth of science and technology, automated burns diagnosis still remains a major challenge. Researchers have been exploring visual images-based automated approaches for burn diagnosis. Noting that the impact of a burn on a particular body part can be related to the skin thickness factor, we propose a deep convolutional neural network based body part-specific burns severity assessment model (BPBSAM).MethodConsidering skin anatomy, BPBSAM estimates burn severity using body part-specific support vector machines trained with CNN features extracted from burnt body part images. Thus BPBSAM first identifies the body part of the burn images using a convolutional neural network in training of which the challenge of limited availability of burnt body part images is successfully addressed by using available larger-size datasets of non-burn images of different body parts considered (face, hand, back, and inner forearm). We prepared a rich labelled burn images datasets: BI & UBI and trained several deep learning models with existing models as pipeline for body part classification and feature extraction for severity estimation.ResultsThe proposed novel BPBSAM method classified the severity of burn from color images of burn injury with an overall average F1 score of 77.8% and accuracy of 84.85% for the test BI dataset and 87.2% and 91.53% for the UBI dataset, respectively. For burn images body part classification, the average accuracy of around 93% is achieved, and for burn severity assessment, the proposed BPBSAM outperformed the generic method in terms of overall average accuracy by 10.61%, 4.55%, and 3.03% with pipelines ResNet50, VGG16, and VGG19, respectively.ConclusionsThe main contributions of this work along with burn images labelled datasets creation is that the proposed customized body part-specific burn severity assessment model can significantly improve the performance in spite of having small burn images dataset. This highly innovative customized body part-specific approach could also be used to deal with the burn region segmentation problem. Moreover, fine tuning on pre-trained non-burn body part images network has proven to be robust and reliable.  相似文献   
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目的:回顾分析应用接骨板螺钉系统、不扩髓肱骨髓内钉系统对肱骨中上段骨折的临床治疗效果。方法:2009年1月~2012年12月,收治肱骨中上段骨折31例。术后随访摄肱骨X光片评价愈合的情况,并应用ASES进行功能评分。结果:所有患者均获随访,随访过程中未发现任何与内固定物有关的并发症。接骨板组骨折愈合时间(7.5±1.2)个月,髓内钉组骨折愈合时间(5.8±1.0)个月,两组比较差异有统计学意义(P<0.01)。接骨板组与髓内钉组术后10个月ASES评分优良率分别为:89.47%、91.66%,两组ASES评分优良率比较差异无统计学意义(P=0.07);其中内固定拆除术后2个月ASES功能评分:接骨板组12例优良率83.33%;髓内钉组2例功能评分:一般。结论:在严格选择手术适应症,规范手术操作,结合术后科学康复训练的前提下,采用接骨板和髓内钉系统均是治疗肱骨中上端骨折有效的治疗方式。髓内钉系统具有手术创伤小、骨折愈合快等优势,术后无特殊不适不建议将髓内钉取出。  相似文献   
10.
通过分析郑寿全《医理真传》,认为郑氏虽为"火神派"的代表,虽然擅用姜、附、桂,但是其更加重视中土脾胃,即贵"中"。贵"中"思想更能代表郑氏的学术思想。提出贵"中"思想可以使我们更加全面地认识和继承郑氏的学术思想。  相似文献   
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